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This study aimed to investigate the potential mitigating effects of N-acyl homoserine lactonase (AHLase) on the virulence of Salmonella typhimuriumand its induction of intestinal damages in broilers. In vitro study was firstly conducted to examine if AHLase treatment could attenuate the virulence of S. typhimurium. Then, an in vivo experiment was performed by allocating 240 broiler chicks at 1 d old into 3 groups (8 replicates per group): negative control (NC), positive control (PC), and PC supplemented with 10,000 U/kg AHLase. All chicks except those in NC were orally challenged by S. typhimuriumfrom 8 to 10 d of age. Parameters were measured on d 11 and 21. The results showed that treatment with 1 U/mL AHLase suppressed the biofilm-forming ability (including biofilm biomass, extracellular DNA secretion and biofilm formation-related gene expression), together with swarming motility and adhesive capacity of S. typhimurium. Supplemental 10,000 U/kg AHLase counteracted S. typhimurium-induced impairments (P < 0.05) in broiler growth performance (including final body weight, average daily gain and average daily feed intake) during either 1–11 d or 12–21 d, and increases (P < 0.05) in the indexes of liver, spleen and bursa of Fabricius on d 11, together with reductions (P < 0.05) in ileal villus height and its ratio to crypt depth on both d 11 and 21. AHLase addition also normalized the increased (P < 0.05) mRNA expression of ileal occludin on both d 11 and 21 in S. typhimurium-challenged broilers. However, neither S. typhimuriumchallenge nor AHLase addition altered (P > 0.05) serum diamine oxidase activity of broilers. Noticeably, S. typhimuriumchallenge caused little change in the mRNA expression of ileal inflammatory cytokines except for an increase (P < 0.05) in interleukin-8 expression on d 11, whereas AHLase addition normalized (P < 0.05) this change. In conclusion, AHLase treatment could attenuate the virulence and pathogenicity of S. typhimurium, thus contributing to alleviate S. typhimurium-induced growth retardation and intestinal damages in broilers.

Using the electrochemical CO2reduction reaction (CO2RR) with Cu-based electrocatalysts to achieve carbon-neutral cycles remains a significant challenge because of its low selectivity and poor stability. Modulating the surface electron distribution by defects engineering or doping can effectively improve CO2RR performance. Herein, we synthesize the electrocatalyst of Vo-CuO(Sn) nanosheets containing oxygen vacancies and Sn dopants for application in CO2RR-to-CO. Density functional theory calculations confirm that the incorporation of oxygen vacancies and Sn atoms substantially reduces the energy barrier for *COOH and *CO intermediate formation, which results in the high efficiency, low overpotential, and superior stability of the CO2RR to CO conversion. This electrocatalyst possesses a high Faraday efficiency (FE) of 99.9% for CO at a low overpotential of 420 mV and a partial current density of up to 35.22 mA cm–2at −1.03 V versus reversible hydrogen electrode (RHE). The FECOof Vo-CuO(Sn) could retain over 95% within a wide potential area from −0.48 to −0.93 V versus RHE. Moreover, we obtain long-term stability for more than 180 h with only a slight decay in its activity. Therefore, this work provides an effective route for designing environmentally friendly electrocatalysts to improve the selectivity and stability of the CO2RR to CO conversion.

Flight behaviours of birds have been extensively studied from different angles such as their kinematics, aerodynamics and, more generally, their migration patterns. Nevertheless, much is still unknown about the daily foraging flight activity and behaviour of breeding birds, and potential differences among males and females. The recent development of miniaturized accelerometers allows us a glimpse into the daily life of a songbird. Here, we tagged 13 male and 13 female pied flycatchers (Ficedula hypoleuca) with accelerometers and used machine learning approaches to analyse their flight activity and effort during the chick rearing period. We found that during 2 h of foraging, chick-rearing pied flycatchers were flying on average 13.7% of the time. Almost all flights (>99%) were short flights lasting less than 10 s. Flight activity changed throughout the day and was highest in the morning and lowest in the early afternoon. Male pied flycatchers had lower wing loading than females, and in-flight accelerations were inversely correlated with wing loading. Despite this, we found no significant differences in flight duration and intensity between sexes. This suggests that males possess a higher potential flight performance, which they did not fully utilize during foraging flights.

Suppressing the recombination of light-induced carriers in semiconductor photocatalysts is crucial but challenging for high-activity photocatalysis. In addition to the current substantially developed strategies, such as the built-in field of catalytic heterostructures, other promising alternatives need to be explored. Herein, a mangosteen peel waste-derived 3D graphene hybrid material with a magnetic interfacial junction was constructed to obtain insights into its highly efficient photocatalytic performance by boosting carrier transfer efficiency with the assistance of a magnetic field. The spin-related behavior of the ferromagnetic alignment of the magnetic interfacial junction of the designed 3D graphene/Cd0.5Zn0.5S hybrids plays an essential role in improving the photocatalytic performance, with ciprofloxacin degradation efficiency reaching 95% removal in 15 min, which is a 67% reduction in photocatalytic degradation time. This photocatalytic performance is outstanding in comparison to previous research without an applied external magnetic field. With low energy consumption, this magnetic field strategy provides a new perspective for water treatment as well as various catalytic fields.

The electrochemical CO2reduction reaction (CO2RR) to HCOOH offers a promising strategy for a carbon-neutral cycle. Sn-Based materials have been demonstrated as applicable in extensive studies of CO2RR to HCOOH, but great challenges still remain, including the weak CO2adsorption and narrow potential window as well as low stability. Herein, we developed ultrasmall Sn nanoparticles inlaid on N/P-doped carbon (Sn@NPC) composites by an upcycling design using Sn electroplating sludge. The obtained Sn@NPC electrode exhibited a higher Faradaic efficiency of 87.93% for HCOOH at 1.05 V vs.RHE and an FE over 80% within a 500 mV broad potential window. Moreover, the Sn@NPC electrode achieved excellent long-term stability up to 105 h, which was superior to that of most Sn-based catalysts in similar systems. Density functional theory calculations demonstrated that Sn@NPC could enhance CO2adsorption, which led to stronger *OCHO adsorption, weaker *HCOOH adsorption and faster electron/mass transport. This work may provide a promising lead for recycling metal from electroplating sludge and for the design of efficient and stable catalysts for the CO2RR.